/**
* Perfoms the load of an entity.
*
* @return The loaded entity.
* @throws HibernateException
*/
protected Object load(
final LoadEvent event,
final EntityPersister persister,
final EntityKey keyToLoad,
final LoadEventListener.LoadType options)
throws HibernateException {
if (event.getInstanceToLoad() != null) {
if (event.getSession().getPersistenceContext().getEntry(event.getInstanceToLoad()) != null) {
throw new PersistentObjectException(
"attempted to load into an instance that was already associated with the session: "
+ MessageHelper.infoString(
persister, event.getEntityId(), event.getSession().getFactory()));
}
persister.setIdentifier(
event.getInstanceToLoad(), event.getEntityId(), event.getSession().getEntityMode());
}
Object entity = doLoad(event, persister, keyToLoad, options);
boolean isOptionalInstance = event.getInstanceToLoad() != null;
if (!options.isAllowNulls() || isOptionalInstance) {
ObjectNotFoundException.throwIfNull(entity, event.getEntityId(), event.getEntityClassName());
}
if (isOptionalInstance && entity != event.getInstanceToLoad()) {
throw new NonUniqueObjectException(event.getEntityId(), event.getEntityClassName());
}
return entity;
}
/**
* Handle the given load event.
*
* @param event The load event to be handled.
* @return The result (i.e., the loaded entity).
* @throws HibernateException
*/
public void onLoad(LoadEvent event, LoadEventListener.LoadType loadType)
throws HibernateException {
final SessionImplementor source = event.getSession();
EntityPersister persister;
if (event.getInstanceToLoad() != null) {
persister =
source.getEntityPersister(
null, event.getInstanceToLoad()); // the load() which takes an entity does not pass an
// entityName
event.setEntityClassName(event.getInstanceToLoad().getClass().getName());
} else {
persister = source.getFactory().getEntityPersister(event.getEntityClassName());
}
if (persister == null) {
throw new HibernateException("Unable to locate persister: " + event.getEntityClassName());
}
EntityKey keyToLoad = new EntityKey(event.getEntityId(), persister, source.getEntityMode());
try {
if (loadType.isNakedEntityReturned()) {
// do not return a proxy!
// (this option indicates we are initializing a proxy)
event.setResult(load(event, persister, keyToLoad, loadType));
} else {
// return a proxy if appropriate
if (event.getLockMode() == LockMode.NONE) {
event.setResult(proxyOrLoad(event, persister, keyToLoad, loadType));
} else {
event.setResult(lockAndLoad(event, persister, keyToLoad, loadType, source));
}
}
} catch (HibernateException e) {
log.info("Error performing load command", e);
throw e;
}
}
/**
* Performs the process of loading an entity from the configured underlying datasource.
*
* @return The object loaded from the datasource, or null if not found.
* @throws HibernateException
*/
protected Object loadFromDatasource(
final LoadEvent event,
final EntityPersister persister,
final EntityKey keyToLoad,
final LoadEventListener.LoadType options)
throws HibernateException {
final SessionImplementor source = event.getSession();
Object entity =
persister.load(event.getEntityId(), event.getInstanceToLoad(), event.getLockMode(), source);
/*if ( entity == null ) {
//remember it doesn't exist, in case of next time
source.getPersistenceContext().addNonExistantEntityKey(keyToLoad);
}*/
if (event.isAssociationFetch() && source.getFactory().getStatistics().isStatisticsEnabled()) {
source.getFactory().getStatisticsImplementor().fetchEntity(event.getEntityClassName());
}
return entity;
}
private Object assembleCacheEntry(
final CacheEntry entry,
final Serializable id,
final EntityPersister persister,
final LoadEvent event)
throws HibernateException {
final Object optionalObject = event.getInstanceToLoad();
final EventSource session = event.getSession();
final SessionFactoryImplementor factory = session.getFactory();
if (log.isTraceEnabled()) {
log.trace(
"assembling entity from second-level cache: "
+ MessageHelper.infoString(persister, id, factory));
}
EntityPersister subclassPersister = factory.getEntityPersister(entry.getSubclass());
Object result =
optionalObject == null ? session.instantiate(subclassPersister, id) : optionalObject;
// make it circular-reference safe
TwoPhaseLoad.addUninitializedCachedEntity(
new EntityKey(id, subclassPersister, session.getEntityMode()),
result,
subclassPersister,
LockMode.NONE,
entry.areLazyPropertiesUnfetched(),
entry.getVersion(),
session);
Type[] types = subclassPersister.getPropertyTypes();
Object[] values =
entry.assemble(
result,
id,
subclassPersister,
session.getInterceptor(),
session); // intializes result by side-effect
TypeFactory.deepCopy(
values, types, subclassPersister.getPropertyUpdateability(), values, session);
Object version = Versioning.getVersion(values, subclassPersister);
if (log.isTraceEnabled()) log.trace("Cached Version: " + version);
final PersistenceContext persistenceContext = session.getPersistenceContext();
persistenceContext.addEntry(
result,
Status.MANAGED,
values,
null,
id,
version,
LockMode.NONE,
true,
subclassPersister,
false,
entry.areLazyPropertiesUnfetched());
subclassPersister.afterInitialize(result, entry.areLazyPropertiesUnfetched(), session);
persistenceContext.initializeNonLazyCollections();
// upgrade the lock if necessary:
// lock(result, lockMode);
// PostLoad is needed for EJB3
// TODO: reuse the PostLoadEvent...
PostLoadEvent postLoadEvent =
new PostLoadEvent(session).setEntity(result).setId(id).setPersister(persister);
PostLoadEventListener[] listeners = session.getListeners().getPostLoadEventListeners();
for (int i = 0; i < listeners.length; i++) {
listeners[i].onPostLoad(postLoadEvent);
}
return result;
}
